CHICAGO (CBS) -- The City Council will vote Wednesday on Mayor Rahm Emanuel's final budget, a $10 billion spending plan that does not rely on any new taxes or fees.

The mayor's 2019 budget is expected to receive overwhelming support from aldermen.

City government still faces a much bigger challenge down the road, however, as pension payments will skyrocket in the next few years.

Pension obligations are set to jump by nearly a third in 2020. Without new revenues, the city's pension debt is expected to balloon to more than $500 million by 2021.

Emanuel plans to lay out a plan to address the city's pension debt next month, possibly by issuing $10 billion in pension obligation bonds. However, a final decision on how to address the city's pension crisis will be up to the next mayor.